/**
 * 
 */
package com.fan.shop.dao;

import java.util.List;

import com.fan.shop.domain.User;

/**
 * @author Fan
 * 
 */
public interface UserDao  {

	public User getUser(String username);

	public List<User> getAllUsers();

	public int getSize();

	public void addUser(User user);

	public void updateUser(User user);

	public void deleteUser(User user);
	
	public boolean hasUser(String username);
	public List<String> getColumnNames();
}
